Reinforcing-bar for concrete.



DONALD MODONLALD, OF LOUISVILLE, KENTUCKY.

REINFORCING-BAR FOR CONCRETE.

Specification of Letters Patent.

Patented Feb. 11, 1913.

Application filed June 21, 1912. Serial No. 705,145.

To all whom it may concern:

Be it known that I, DONALD MCDONALD, acitizen of the United States, residing at Louisville, in the county of Jefferson and State of Kentucky, have invented certai'n new and useful Improvements in Reinforcing-Bars for Concrete, of which the following is a specification.

The object of my invention is to provide a reinforce for concrete construction comrising a series of bars, each bar being ormed with rojections constructed to interlock with similar projections on another bar, and fastenings securing the bars to gether at their intersection.

' In the drawing, Figure 1 is a longitudinal elevation of a bar embodying my invention; Fig. 2 is a longitudinal section of the same; Fig. 3 is a section on the line 3-3, Fig. 1; Fig. 4: is a section on the line IE-4, Fig. 1'; Figs. 5 and 6 are assembly views showing bars coupled together; Fig. 7 is a bottom plan view of one of the fastening means; Fi 8 is a detail view showing the triangles lightened; Fig. 9 is a detail view showing the triangular projections on one side of the bar only.

-While the bar may be of any approved shape, I prefer to construct it as per the cross-sectional views shown in Figs. 3 and 4, by rolling the metal through suitable rolls, so that the bar is completely formed in the process of rolling. It will be noted that the sides of the bar are beveled so as to clear the rolls of the mill through which the bar is passed. The projections on the bar, to be hereinafter referred to, are also beveled on their edges for the same reason.

1 represents the bar on which are formed, by the process of rolling, right angle triangles 2 and seats 3 and 4. The right angle triangles are arranged in pairs so as to provide the recess or seat 3 at right angles to the longitudinal axis of the bar, and the seat- 4 at an oblique angle, for instance the an le at 45 degrees, to the longitudinal axis of the bar, so that the reinforce may be constructed by the use of these bars without bending or deflecting the bars. I prefer to construct the projections as right angle triangles whose basesand altitudes are equal to the width of the bar, and to space them as shown in Fig. 1. It will be seen that by placing the com panion bar in the seat 3, the two bars are mortised together at right angles; by placing the companion bar the seat 4, the bars are secured together at an angle of 45 degrees, as shown in Fig. 6.

\Vhen the bars are fitted together in the desired position, they are prevented from separating by any suitable device which will hold them together. They may be wrapped with wire, or a plate of iron may be placed on each side of the joint with two or more bolts holding the plates together on the bars. I prefer to join the bars together at their intersection by means of clips 5, as shown in Fig. 7, said clipsbeing provided with mortises 6 and 7 adapted to engage a corner of the right angle triangle projections on the respective bars. These plates are provided with bolt openings 8, whereby they may be firmly clamped to the bars. By reventing the separation of the bars, and y properly proportioning the amount of metal in the projections to the size of the bar, every joint can be made as strong, if not stronger, than the bar itself.

The four positions in which companion bars may be placed relative to each other, as can be seen from the drawing, lend this particular construction of bar to, a great many constructions. For instance, the frame of a structure can be set up and braced. A truss can be made of almost any span, as the top chords and bottom chords can 7 be built up of three or more bars to any length desired. Used as a concrete reinforcement, the projections on the bars furnish an excellent hold to prevent the bars slipping in theconcrete. They allow reinforcement at right angles or at any desired angle and permit the building up of truss rod reinforcement for concrete beams.

For the purpose of my invention, itis not necessary to roll any special bar, but only to select bars of such size and in such number as to get the strength required in the bottom chord, and insert into them bars of proper length, proper size and proper number to make the angle members each project up from the bottom chord to the height dewhich will, as stated, mesh with each other, although one may be several times heavier than the other, inasmuch asthe bevel on all case the diagonally disposed edge of the triangle will serve as a tension member to prethe bars will be formed on the same angle.

The sides of the bar may be curved, if desired, including the edges of the projections on the bar. If desired, considerable metal may be taken out of the triangle, in which vent the bar pulling in two, and at the same time leave the projections with sufiicient bearing strength and sufficient shearing strength to develop the full tensile strength of the ham I If preferred or found necessary, the bar may be formed with triangular projections on one side only, but in this case, I prefer to increase and balance the hold of the barin concrete, by forming ordinary corrugations on the opposite side of the bar, as

of each in alinement with one side of the bar and the inclined sides parallel to each other and inclined to the axis of the bar, the distance between any two projections being the same width, whereby seats are formed on the bar at right and oblique angles to the longitudinal axis of the bar.

2. A bar for reinforcing concrete having one or more faces provided with a-series of right angle triangular projections; each projection arranged with its base in alinement with one side of t e bar and its inclined side inclined to th axis of the bar, and every projection having its inclined side parallel with the inclined side of an adjacent projection, and its third side which is at right angles to the longitudinal axis of the bar parallel with the corresponding side of an adjacent projection.

The foregoing specification signed at Louisville, Kentucky.

DONALD MCDONALD;

Inpresence of- F. W. MIL ER, WM. H. CRUTGHIN.

Copies of'this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

' Washington, D. O. 

